/*
 * Copyright (c) 2007-2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.org.apache.bcel.internal.generic;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache BCEL" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache BCEL", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import com.sun.org.apache.bcel.internal.classfile.*;

/**
 * This class represents an exception handler, i.e., specifies the  region where
 * a handler is active and an instruction where the actual handling is done.
 * pool as parameters. Opposed to the JVM specification the end of the handled
 * region is set to be inclusive, i.e. all instructions between start and end
 * are protected including the start and end instructions (handles) themselves.
 * The end of the region is automatically mapped to be exclusive when calling
 * getCodeException(), i.e., there is no difference semantically.
 *
 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
 * @see     MethodGen
 * @see     CodeException
 * @see     InstructionHandle
 */
public final class CodeExceptionGen implements InstructionTargeter, Cloneable, java.io.Serializable {
    private InstructionHandle start_pc;
    private InstructionHandle end_pc;
    private InstructionHandle handler_pc;
    private ObjectType catch_type;

    /**
     * Add an exception handler, i.e., specify region where a handler is active and an
     * instruction where the actual handling is done.
     *
     * @param start_pc Start of handled region (inclusive)
     * @param end_pc End of handled region (inclusive)
     * @param handler_pc Where handling is done
     * @param catch_type which exception is handled, null for ANY
     */
    public CodeExceptionGen(InstructionHandle start_pc, InstructionHandle end_pc, InstructionHandle handler_pc, ObjectType catch_type) {
        setStartPC(start_pc);
        setEndPC(end_pc);
        setHandlerPC(handler_pc);
        this.catch_type = catch_type;
    }

    /**
     * Get CodeException object.<BR>
     *
     * This relies on that the instruction list has already been dumped
     * to byte code or or that the `setPositions' methods has been
     * called for the instruction list.
     *
     * @param cp constant pool
     */
    public CodeException getCodeException(ConstantPoolGen cp) {
        return new CodeException(start_pc.getPosition(), end_pc.getPosition() + end_pc.getInstruction().getLength(), handler_pc.getPosition(), (catch_type == null) ? 0 : cp.addClass(catch_type));
    }

    /* Set start of handler
     * @param start_pc Start of handled region (inclusive)
     */
    public final void setStartPC(InstructionHandle start_pc) {
        BranchInstruction.notifyTargetChanging(this.start_pc, this);
        this.start_pc = start_pc;
        BranchInstruction.notifyTargetChanged(this.start_pc, this);
    }

    /* Set end of handler
     * @param end_pc End of handled region (inclusive)
     */
    public final void setEndPC(InstructionHandle end_pc) {
        BranchInstruction.notifyTargetChanging(this.end_pc, this);
        this.end_pc = end_pc;
        BranchInstruction.notifyTargetChanged(this.end_pc, this);
    }

    /* Set handler code
     * @param handler_pc Start of handler
     */
    public final void setHandlerPC(InstructionHandle handler_pc) {
        BranchInstruction.notifyTargetChanging(this.handler_pc, this);
        this.handler_pc = handler_pc;
        BranchInstruction.notifyTargetChanged(this.handler_pc, this);
    }

    /**
     * @param old_ih old target, either start or end
     * @param new_ih new target
     */
    @Override
    public void updateTarget(InstructionHandle old_ih, InstructionHandle new_ih) {
        boolean targeted = false;

        if (start_pc == old_ih) {
            targeted = true;
            setStartPC(new_ih);
        }

        if (end_pc == old_ih) {
            targeted = true;
            setEndPC(new_ih);
        }

        if (handler_pc == old_ih) {
            targeted = true;
            setHandlerPC(new_ih);
        }

        if (!targeted)
            throw new ClassGenException("Not targeting " + old_ih + ", but {" + start_pc + ", " + end_pc + ", " + handler_pc + "}");
    }

    /**
     * @return true, if ih is target of this handler
     */
    @Override
    public boolean containsTarget(InstructionHandle ih) {
        return (start_pc == ih) || (end_pc == ih) || (handler_pc == ih);
    }

    /** Sets the type of the Exception to catch. Set 'null' for ANY. */
    public void setCatchType(ObjectType catch_type) {
        this.catch_type = catch_type;
    }

    /** Gets the type of the Exception to catch, 'null' for ANY. */
    public ObjectType getCatchType() {
        return catch_type;
    }

    /** @return start of handled region (inclusive)
     */
    public InstructionHandle getStartPC() {
        return start_pc;
    }

    /** @return end of handled region (inclusive)
     */
    public InstructionHandle getEndPC() {
        return end_pc;
    }

    /** @return start of handler
     */
    public InstructionHandle getHandlerPC() {
        return handler_pc;
    }

    @Override
    public String toString() {
        return "CodeExceptionGen(" + start_pc + ", " + end_pc + ", " + handler_pc + ")";
    }

    @Override
    public Object clone() {
        try {
            return super.clone();
        } catch (CloneNotSupportedException e) {
            System.err.println(e);
            return null;
        }
    }
}
